1. Field of the Invention
The present invention relates to a cloth cutting device in a button-hole sewing machine, and more particularly to a cloth cutting device for cutting a piece of cloth to make a button hole or the like before the button hole or the like is sewn.
2. Description of the Prior Art
A button-hole sewing machine for forming button holes such as eyelet holes is well known in the art. A sewing machine of this type is provided with a cloth cutting device which cuts a piece of cloth along the contour of a desired button hole before or after the button hole is sewn.
In such a conventional cloth cutting device, a moveable knife is mechanically driven by the utilization of the drive force of a main cam, so that a piece of cloth is cut by the cooperation of the moveable knife with a stationary knife. In a conventional device the moveable knife is driven by a mechanical drive source, namely, the main cam as described above. Therefore, the stroke of the moveable knife can be adjusted, but the operating speed or pressure of the moveable knife cannot be adjusted.
In other words, the operating speed of the moveable knife is determined indiscriminately from the sewing speed of the sewing machine, and the operating pressure of the moveable knife is defined by the operating speed. Accordingly, the operating speed and the operating pressure cannot be adjusted. Therefore, components, including these knives may be broken, and sometimes the piece of cloth cannot be cut very well.